Programming Fundamentals Exam 1 - Chapter 3

You can use this method to display formatted output in a console window.

System.out.printf

briefly describe how the && operator works

answers may vary. use your own words

briefly describe how the || operator works

answers may vary. use your own words

what happens when you compare two string objects with the == operator

an error will occur. you have to use .equals for strings

This type of expression has a value of either true or false.

boolean expression

to create a block of statements, you enclose statements in these

braces

explain what is meant by the phrase "conditionally executed"

conditionally executed means that the statements will not execute if the condition preceding it is false

This section of a switch statement is branched to if none of the case expressions match the switch expression.

default

true or false: a conditionally executed statement should be indented one level from the if clause

true

true or false: all lines in a conditionally executed block should be indented one level

true

true or false: when an if statement is nested in the else clause of another statement, the only time the inner if statement is executed when the boolean expression of the outer if statement is true

true

true or false. the = operator and the == operator perform the same operation

false

This is a boolean variable that signals when some condition exists in the program.

flags

what risk does a programmer take when not placing a trailing else at the end of an if-else-if statement

if the user enters something that does not apply to any of the if-else-if statements, the code will simply stop running and produce no output

find the error: if (average = 100) System.out.println("Perfect Average!")

it is missing an additional ==

why is it good advice to indent all of the statements inside a set of braces

it makes the code easier to read, and it helps the programmer know which statements go with the conditional statement

assume that partNumber references a string object. the following if statement should perform a case-insensitive comparison. what is wrong with it: if (partNumber.equals("BQ789W4")) available = true;

it needs to add IgnoreCase after .equals

the following statement assigns 0 to z if a is less than 10; otherwise it should assign 7 to z. what is wrong with it: z = (a < 10) : 0 ? 7

it should look like: if (a < 10) z = 0; else z = 7;

&&, ||, and ! are

logical operators

This is an if statement that appears inside another if statement.

nested if statement

This is an empty statement that does nothing.

null statement

true or false: when an if statement is nested in the if clause of another statement, the only time the inner if statement is executed is when the boolean expression of the outer if statement is true

true

true or false: the scope of a variable is limited to the block in which it is defined

false

when determining whether a number is inside a range, its best to use

&&

How does the character 'A' compare to the character 'B'?

A is less than B

explain why a misplaced semicolon can cause an if statement to operate incorrectly

semicolon are used when it is it the end of a statement and java will treat the if statement like a single statement and throw an error or skip over the statements that are meant to be executed within the if statement

how often must you place break; statements when using a switch statement

after every case and the default

The if statement is an example of a __________.

decision structure

>, <, and == are

relational operators

the following statement should determine whether x is not greater than 20. what is wrong with it: if (!x > 20)

the ! is supposed to be beside the >

the following statement should determine whether count is outside the range of 0to100. what is wrong with it: if(count < 0 && count > 100)

the && means and, and we are looking for the statement to check if the count < 0 OR count > 100

An else clause always goes with __________.

the closest previous if clause that doesn't already have its own else clause

what is wrong with the following code: double value = 12345.678; System.out.printf("%.2d", value)

the d in "%.2d" needs to be an f

This determines whether two different String objects contain the same string.

the equals method

explain the purpose of a flag variable

the purpose of a flag variable is to determine whether to boolean expression is true or false

find the error: if (x==1); y=2; else if (x ==2); y=3; else if (x==3); y=4;

the semicolon after each if/else if statement will cause the following statements to be ignored, and the code will not run

the following statement should determine whether count if within the range of 0to100. what is wrong with it: if (count >= 0 || count <= 100)

the || means or, and we are looking for the statement to check if the count is >= 0 AND count <= 100

find the error: if (num2 == 0) System.out.println("Division by zero is not possible. "); System.out.println("please run the program again"); System.out.println("and enter a number besides zero");

there are no braces

the conditional operator takes this many operands

three